CBSE Exam 2023 with Complete Solutions

Alkaptonuria - ANSWER-Absence of homogentisate oxidase - arthritis - discolored sclerae and other areas (ear cartilage) - Dark urine - spinal disc degeneration and dense calcifications possible What is the cause of "bitter almond" breath? - ANSWER-Cyanide poisoning What does cyanide inhibit? - ANSWER-Cytocrhome oxidase in the ETC What is the treatment for cyanide poisoning? - ANSWER-Amyl nitrate (oxidizes hemoglobin to methemoglobin, which strongly binds cyanide) 6 month old child with frequent infections and carpopedal spasm and facial spasm upon tapping - ANSWER-DiGeorge Syndrome - hypoparathyroidism and T-cell deficiency Hypocalcemia is what causes the spasms CATCH22 pneumonic: Chromosome 22, Abnormal facies, Thymic hypoplasia, Cleft palate, and Hypocalcemia Young (27 yrs old) man with lots of atherosclerotic plaques and small, raised yellow-brown lesions on extensor surfaces of arms - ANSWER-Familial hypercholesterolemia (FH) Inherited disorder that causes high serum cholesterol levels the lesions are xanthomas caused by deposits of the cholesterol A baby is born with severe abnormalities, including prominent epicanthal folds, up slanting palpebral fissures, and macroglossia. He also has thick skin at the nape of the neck He vomits greenish material immediately after eating - ANSWER-Down Syndrome The vomiting is due to GI disorder which they often have Boy is born with flat feet, long face, large ears, and an abnormal appearing X-chromosome - ANSWER-Fragile X syndrome Expansion of a CGC trinucleotide repeat sequence on the X chromosome X-linked genetic The most common cause of mental retardation is - ANSWER-Fragile X syndrome A baby begins to get sick after weaning from breast milk, and has a low glucose level which is not lost in urine - ANSWER-Fructose intolerance Fructose-1-phosphate levels will be elevated in liver cells A 12 year old intellectually disabled boy presents with vision difficulties. Exam reveals bilateral dislocated lenses and a tall, thin body habitus. Labs show increased levels of serum methionine and serum homocysteine - ANSWER-Homocysteinuria caused by cystathionine synthase Also at risk for CV disease and osteoporosis HOMOCY Homocyteine in urine, osteoporosis, marfoid habitus, ocular changes, kYphosis Can also be intellectually disabled 1 year old presents with abnormalities. PE reveals developmental delay, coarse facial features, skeletal abnormalities, umbilical hernia, corneal clouding. Baby's liver and spleen are enlarged, and the joints are stiff - ANSWER-Hurler Syndrome One of the mucopolysaccharidoses diseases Caused by alpha L-iduronidase defect (can't break down dermatin sulfate and heparan sulfate - accumulates in tissues) Hunter's Syndrome vs Hurler's Syndrome - ANSWER-Hunters = mild Hurler's + aggressive behavior, no corneal clouding 2 year old with mental retardation and restricted joint movement. PE reveals coarse facial features and clouded corneas. Blood tests reveal elevated lysosomal enzymes in the serum. Parents are first cousins - ANSWER-I-cell disease Similar to Hurler syndrome but with findings at birth First cousins just says that there is an increased risk of an autosomal recessive trait being passed Mutation of the golgi apparatus which keeps a marker from being added to proteins destined for lysosomes Lysosomes accumulate non-degradable material and the lysosomal enzymes from the golgi are secreted from the cell, showing up in the blood Man is infertile and history reveals repeated sinus infections and a chronic cough - ANSWER-Kartagener syndrome Immotile cilia due to a dynein arm defect Causes immotile sperm; respiratory cilia also need dynein for proper function 2 year old begins biting fingers and scratching face incessantly - has become increasingly irritable. Mother reports orange "sand" in diaper. Serum uric acid level of 55 mg/dL. Urinalysis reveals crystalluria and microscopic hematuria - ANSWER-Lesch-Nyhan syndrome Caused by deficiency in HGPRT Can also be an acronym! H = Hyperuricemia G = Gout P = Pissed off R = Retardation T = dysTonia Hyperuricemia is what causes the orange "sand" The treatment for Lesch-Nyhan syndrome is - ANSWER-Allopurinol Inhibits xanthine oxidase, preventing formation of uric acid 19 year old female presents with extreme muscle aches after working out. Urine is the color of "cherry soda pop" Labs reveal serum creatinase level of 93970 IU/L. Urine positive for myoglobin - ANSWER-McArdle's disease (Type V glycogen storage disease) No increase in lactic acid after working because lactic acid is a product of glucose/glycogen metabolism Cherry soda pop urine is due to myoglobinuria from muscles breaking down due to lack of glucose, as well as elevated creatine kinase Patient is not diabetic but experiences severe hypoglycemia between meals - ANSWER-Von Gierke disease ( Type I glycogen storage disease) Caused by a deficiency in Glucose-6-phosphate Patient has extreme exercise intolerance and dies at a young age due to heart failure - ANSWER-Pompe disease (Type II glycogen storage disease) Due to deficiency in lysosomal acid alpha 1,4, glucosidase activity PomPe trashes the PumP (1,4) (heart, liver, and muscle) What is a milder version of Von Gierke's disease? - ANSWER-Cori disease (Type III glycogen storage disease) 2 year old presents due to poor development as well as vomiting, irritability, and a skin rash. Mother says his urine has a strange "mousy" odor. He has a surprisingly fair-skinned complexion compared to the rest of his family. PE reveals hypertonia, hyper reflexiveness, and an eczema-like rash. - ANSWER-Phenylketonuria Findings: intellectual disability, growth retardation, seizures, fair skin, eczema, musty body odor Deficiency in metabolism of phenylalanine -- leads to excess phenyl ketones in blood (musty odor) What are the only purely ketogenic amino acids? - ANSWER-Leucine and lysine 6 month old presents b/c she's feeding poorly and has been lethargic for several months. Breaths more rapidly than normal and recently had a seizure. Serum pH of 7.2, an anion gap of 19 mEq/L, elevated levels of pyruvate and alanine, and decreased levels of citrate - ANSWER-Pyruvate dehydrogenase deficiency As glycolysis happens, pyruvate is created, but it cannot be converted to Acetyl-CoA due to a deficiency in pyruvate dehydrogenase. As pyruvate accumulates, some is converted into lactate to regenerate NAD+. The elevated lactate level is responsible for the acidosis and anion gap observed. Alanine levels are high because excess pyruvate is converted to alanine and citrate is low because there is no Acetyl-CoA to combine with oxaloacetate to form citrate (Citric Acid Cycle!) 5 month old of Ashkenazi Jewish descent presents for concerns about developmental regression. Developed normally for 4 months, but can no longer roll over by herself. No longer smiles. PE reveals a cherry-red spot in the macula. - ANSWER-Tay-Sachs disease A disease of sphingolipids, caused by hexosaminidase A Disease is a lysosomal storage disease (enzyme HA is located in the CNS) and accumulation of lipid (GM2) causes progressive neurodegeneration) Children become blind and deaf before paralysis ultimately sets in. Children usually die by 3 years of age How is Niemann-Pick disease different from Tay-Sachs disease? - ANSWER-Niemann-Pick involves hepatosplenomegaly Both have the red spot in the macula and both have a poor prognosis Foam cells are a characteristic of N-P Onion-like lysosomes are a characteristic of T-S What disease other than Tay Sachs has an affinity for Ashkenazi Jews? - ANSWER-Gaucher disease (also a sphingolipid disease) Most common of the diseases Has Gaucher cells (look like crumpled tissue paper) 36 year old man presents with shortness of breath. Admits to extensive history of alcoholism. Experiences tingling and burning in his legs for past several weeks. PE reveals he is tachycardia, has rales bilaterally, and has bilateral pitting edema. Also has decreased sensation in his feet and is hypo reflexive in his lower extremities. An x-ray of his chest shows an enlarged cardiac silhouette and bilateral pulmonary congestion. - ANSWER-Vitamin B1 deficiency -- common in alcoholic and malnourished patients Brain and heart affected first Patient is experiencing BOTH dry and wet beribi Wet beribi: high-output congestive heart failure and dilated cardiomyopathy Dry beribi: peripheral neuropathy consisting of muscular atrophy and diminished sensation and reflexes (You'll see this in B12 deficiency but no wet beribi) THINK BER1B1 to remember B1 Patient could also end up suffering from Wernicke encephalopathy and Wernicke-Korsakoff syndrome What are Wernicke encephalopathy and Wernicke-Korsakoff syndrome? - ANSWER-WE: the CNS manifestation of thiamine deficiency. Nystagmus, ophthalmoplegia, and cerebellar ataxia. When the additional symptoms of confusion/psychosis and confabulation are seen, the disease is known as W-K syndrome. It is standard practice to give thiamine before glucose to any patient with suspected thiamine deficiency to prevent Wernicke-Korsakoff Giving glucose before thiamine can cause precipitation and the above diseases 6 month old presents after having a seizure. 5 month history of restlessness, vomiting, and sweating that most commonly occur between meals and subside after feeding. PE reveals baby is small for her age, with a protuberant abdomen, liver below costal margin, and xanthomas on buttocks. Ultrasound shows hepatomegaly and bilaterally enlarged kidneys. Serum glucose is 20, Lactic acid is 9, anion gap is 35 - ANSWER-Von Gierke's disease Type I Glycogen storage disease Deficiency in Glucose-6-phosphatase causing poor glucose control and marked fasting hypoglycemia Hyperlipidemia - especially hypertriglyceridemia - is also common and can lead to xanthoma formation and pancreatitis Nephropathy can occur from accumulation of glycogen in the kidney Extended wearing of contact lenses is the number one risk factor for what? - ANSWER-Acanthamoeba Differentiate between bacterial keratitis and amoeba keratitis - ANSWER-Unlike bacterial keratitis, keratitis from Acanthamoeba takes days or weeks to cause symptoms Initial symptoms of acanthamoeba are redness and feeling of foreign body in eye; blurry vision may be present How is acanthamoeba of the eye diagnosed? - ANSWER-Slit-lamp examination Treatment for acanthamoeba keratitis is what? - ANSWER-Topical antimicrobials such as miconazole and neomycin for several months What are two gram positive spore forming bacteria? - ANSWER-Bacillum anthrax and Clostridium species A widened mediastinum is characteristic of what bacterial infection? - ANSWER-Oral inhalation of bacillus anthrax (Woolsorter's disease) The most common helminthic infection worldwide is - ANSWER-Ascariasis (roundworm) Found in southern United States and tropical climates Eosinophilia is a classic finding in helminth infection Eosinophilia is a classic finding in what type of infection? - ANSWER-Helminth infection What is the drug of choice for nematode infections? - ANSWER-Bedazzle family Disrupt helminthic microtubule synthesis, which weakens cell structure If you see description of "fungus ball" or circular mobile lung mass within preexisting cavitary lesions in the lungs think what? - ANSWER-Aspergillus infection -- specifically called aspergilloma If you see 45 degree branching septa found on bronchoalveolar lavage, think what? - ANSWER-Aspergillus What is the initial presentation for botulinum toxicity? - ANSWER-First, GI distress Then, neurologic symptoms starting with cranial nerves causing blurred vision, decreased eye movements, and a decreased gag reflex What is the presentation for Chagas disease? - ANSWER-It will most likely be in a person who is from southern US, Mexico, or central/south america Patient typically has heart block, ventricular tachycardia, and dilated cardiomyopathy Dilation of the esophagus and colon can cause difficulty swallowing and constipation Romana sign is seen with acute form -- unilateral periorbital edema and conjunctivitis In acute form there can also be a hard red area called a chagoma at the parasite's site of entry into the host